Electrical Problem - Coil?

[dpr17]

1988 Correct Craft Barefoot Nautique - 351 PCM, Won't Start. Thanks to reading all these forums, I was able to get this far....
I believe it's the coil, but why would the coil suddenly fail after sitting all winter? At first I assumed fuel problem and began pumping out old fuel, and checking carb. Carb has good pump shot (rebuilt last year). Gave it a whiff of starting fluid and got nothing. At that point started looking at spark and ignition. Pulled a plug and cranked it - no spark. Worked back to the coil/cap wire, no spark to a good ground except when you actually touch it to the ground (very weak). Checked voltage at + side of coil, 5.6v with key on. Same at resistor block. 10-11v at the red side of resistor block. Cleaned some small debris off the points and adjusted - there is a spark at the points when cranked. Ran a jumper from solenoid directly to + side of coil, and cranked. Still no spark. At that point I assume its the coil. BTW, battery was on the charger through all this-fully charged.

One other thing-I had a depth finder stolen out of the boat and they did pull on wires under the dash. Checked all out and had to recrimp a couple of wires back to accessory circuit breakers. Could a dash short have killed the coil?

Tried emailing SKIDIM but haven't heard. They were closed for spring break. Also posted over at CorrectCraftFan.com. Any help or ideas would be appreciated.

[TRDon]

RE: Electrical Problem - Coil?

A coil replacement is a cheap venture. I would try that. A coil is one of those things that just works or just doesnt. They just go dead spur of the momnet like.

[jward]

RE: Electrical Problem - Coil?

if you have access to a volt meter just trace it from your battery until you find where power is not going

[core-rider]

RE: Electrical Problem - Coil?

Like was said earlier... A coil works or doesn't work, there is no in between. If you have 5.6 VDC at the + post on the coil all wiring should be okay. Try replacing the coil. They are cheap enough and that is more than likely the culprit.

[dpr17]

RE: Electrical Problem - Coil?

Thanks for the quick replies. I do have 5.6vdc at the +coil. Spoke to someone who gave me a lesson in points, so I want to check those as well, but I think its the coil, too. So the ballast resistor steps the voltage down from 12 to 5.6? I had trouble finding that specification.
Thanks again. Hope to work on it tonight! This work thing really cramps my boating style.
Don

[bobchris]

Re: RE: Electrical Problem - Coil?

Like was said earlier... A coil works or doesn't work, there is no in between. If you have 5.6 VDC at the + post on the coil all wiring should be okay. Try replacing the coil. They are cheap enough and that is more than likely the culprit.

sorry but that's not enough voltage to fire the coil, needs to be around 9-10 with a ballast resitor or 12 without one otherwise you can replace it all day long and still not get them to fire. If he has just replaced the points they need sparked or throw in the trash and replaced with an electronic dist.

[Andrew]

RE: Re: RE: Electrical Problem - Coil?

the coil on my 86 receives 6volts. i did rewire the resistor and solenoid so that the coil sees 12v at start, but 6v is perfectly normal

[bobchris]

Re: RE: Re: RE: Electrical Problem - Coil?

the coil on my 86 receives 6volts. i did rewire the resistor and solenoid so that the coil sees 12v at start, but 6v is perfectly normal

well if that's what you think that's fine, but you won't have a very hot spark with that kind of voltage going to the coil, odd's are it wasn't measured correctly but ok if it works it works, what do I know never learned anything while I was designing ignition systems in the 80-90's but I do have a few 100 thousand systems still on the road today.

[Andrew]

RE: Re: RE: Re: RE: Electrical Problem - Coil?

ok....

[core-rider]

RE: Re: RE: Re: RE: Electrical Problem - Coil?

bobchris, you may have a few 100 thousand ignition systems on the road designed your way, but there is no need for that much voltage though a set of points. 5-6 VDC will do just fine. My 84 have about that before I changed the points to electronic and it worked fine. I just wanted the reliability of a breakerless ignition.

dpr17, one thing I forgot to mention. If you upgrade the coil it may not work with thelimited voltage fromthe ballast resistor. When I replaced mine it would not start unless the resistor was taken out. I'm not sure if it was a result of going breakerless or just the newer coil. Just a heads up.

[bobchris]

RE: Re: RE: Re: RE: Electrical Problem - Coil?

depending on the coil it can have a built in resistor so that you don't have to use the ballast resistor. the voltage step down is usually 8-9V from 12 with points but to each there own.

[boatech]

Re: RE: Electrical Problem - Coil?

Like was said earlier... A coil works or doesn't work, there is no in between. If you have 5.6 VDC at the + post on the coil all wiring should be okay. Try replacing the coil. They are cheap enough and that is more than likely the culprit.

this is not true a coil can work but be weak (causing hard start or missfire) you can by an inline kv coil tester for like 15 bucks. a coil on that motor will need to produce atleast 20kv to get it going. simple and easy check check for voltage at + on coil if ok take a test light and place it on the ground terminal of coil crank engine if test light blinks you know the points are good and you have a coil issue. if the test light does not blink while cranking the points are the proplem. i would put 12v to post side of coil just to the the ballast rest. out of the loop because i dont like that fact your trying to fir ethe coil with 5 volts either.

[dpr17]

RE: Re: RE: Electrical Problem - Coil?

Update: After talking to Vince and Tom at SKIDIM with the ideas everyone in this group had, I decided to swap out the points for the electronic ignition drop in. It requires a different coil, which I had planned to buy anyway (and yes you have to bypass the ballast) so I did both at the same time. Parts came today, dropped them in, and 1/2 hour later, she fired up in about 5 seconds!! Tomorrow my girl gets an oil change, new plugs, and a run on the lake!
Thanks everyone for your help, suggestions, and ideas!! I put a photo up in the member section.
Don
1988 BFN